Cauda:
can be separated by two intra-caudal crests. The anterior one is narrow, slightly deep and concave, turning upwards, meeting the deep and wide middle section at angles of > 90 degrees The down-turned section of the cauda is wider and oriented diagonally;

Ostio-caudal differentiation:
dorso-ventrally constricted;

Collum:
absent;

Crista superior:
poorly developed over ostium, ridge-like over anterior portion of the cauda;

Crista inferior:
poorly developed under ostium, well developed under cauda;